Field of the Invention
Exemplary embodiments of the present disclosure relate to a method and system for determining causes of engine stop and, particularly, to a method and system for determining causes of engine stop using ignition power monitoring that determines whether an engine is stopped by a key-off operation or if the engine is stopped due to ignition power failure through ignition power monitoring.
Description of Related Art
For vehicles, an Electronic control unit (ECU) stores abnormal conditions of each component as Diagnostic Trouble Codes (DTCs). Each DTC is utilized to check and repair the vehicle.
For example, failure causes of the vehicle may be easily understood by identifying the DTC through a scanner when the vehicle is serviced.
However, since some abnormal condition may not be recorded as a DTC, there is no easy way to address these problems.
For example, since the ECU does not have logic for determining whether an engine is normally stopped due to a key-off operation by a driver or if the engine is stopped due to ignition power failure, there is no easy way to address such a problem.
That is, ignition power monitoring is not carried out in the ECU. However, the ECU does control operation of the engine when starting and driving. However, when the ignition power fails in the middle of driving, the engine is stopped. In this case, even though the ignition power is normal, the ECU and DTCs do not help to determine whether the engine stop is generated due to: actual failure of the ignition power; a key-off operation; or mal-operation by the driver. The key-off operation of the driver represents an action in which the driver stops the engine by intentionally turning an ignition key or pushing a button ignition key. The mal-operation of the driver represents a key-off action in which an ignition button is pushed by driver or passenger mistakenly or an ignition key bundle is unintentionally turned by weight of a key ring with the ignition key.